Electric switching device



Apri 6, 1926. 1,579,232

' J. l MILTON ELECTRIC SWITCHING DEVICE Filed April 17, 1922 P INVENTOR.

Patented Apr. 6, 1926.

UNITED, STATES i v 1,579,232 PATENT OFFICE.

J'OHN L. MILTON, OF LOUISVILLE, KENTUCKY, ASSIGNOR TO CHEATHAM ELECTRICSWITCHING DEVICE COMPANY, OF LOUISVILLE, KENTUCKY, ACORPORATION'OFKENTUCKY.

ELECTRIC swrronme DEVICE.

Application filed April 17, 1922. Serial No. 554,299. I

To all whom it may concern: 7

Be it known that I, JOHN L. MILTON, a citizen of the United States, anda resident of Louisville, county of Jefferson, and

State of Kentucky, have invented a new and useful Improvement inElectric Switching Devices, of which the following is a specification.

The object of my invention is to provide 10 a solenoid for operating thetongues of switches that will produce a superior draw bar pull withinthe space available in the present type of devices. A further object isto construct a more durable and less ex pensive equipment. These andother objects are accomplished by my invention. An embodiment ishereinafter set forth.

For a more complete description of my in vention, reference is to be hadto the accompanying drawing, forming a part thereof, in

which Figure 1 is a view of the complete equipment, partly in crosssection and partly in full elevation with parts broken away to show thestructure.

Figure 2 is a diagrammatic representation of the application of the coilrepresented by Figure 1.

In the embodiment of my invention herein represented, a simplenon-magnetic tube 1 mounted into a magnetic shell 2, an end piece 3 isin turn tightly mounted into said shell, this structure being so puttogether that it is hermetically sealed with a view of preventing theingress of any foreign substance, 4 is a plunger which is mounted withinthe non-magnetic tube 1, 4 is a magnetic member of this plunger, 4 is anon-magnetic member, 5 and 6 represent solenoids wound directly on tothe tube 1, and properly insulated there-from in any of the well knownmethods. 7-8 and 9 represent magnetic washers of sufficient proportionto carry the magnetic flux set up by passing of electric current thruthe respective coils 5-6.

As current is sent into the coils 5 or 6 the plunger 4 is actuated. Thecoils are wound directly on to the central tube which has beenpreviously prepared for mounting into the casing 2 and end 3 togetherwith the insulation and the magnetic members 78 and 9. After this hasbeen done the impregnation and surface insulation is added. The solenoidin this complete form is now mounted into the case 2 and the end member3 substa-ntially as shown.

In coils of this class as now constructed it is customary to make thesecoils on bobbins separately and then mount them on to the tube loosely.The means of holding these loosely mounted coils in place has been quitean expense and a problem to make suitable holding devices, such ascollars and heavy springs, which apply pressure to the end insulation ofsaid coil. This has lead to trouble from this pressure together with theheating and cooling of the coils which result into expansion andcontraction and cause electrical break downs. The novel system set forthabove saves very considerable expense, insures an absolute predeterminedalignment of the coils and eliminates a large part of the air spacebetween the inner convolutions of the coil and the plunger, therebymaking a very superior coil which increases the effective draw bar pullof the plunger approximately 47%.

The magnetic shell 2 with its end pieces 5 forms a cylinder which is inits completed form mounted into what is known in the art as a groundbox, linkage as shown in Figure 1 and 2 are employed to connect theplunger to the, tongue of the switch so that it will operate from oneposition to another according to whether coil 5 0r 6 is energized.

While other detailed embodiments of this invention may be made it isobvious that it is not restricted thereto. and I do not limit myself tothe structure as shown. I wish to cover the scope of this inventionaccording 90 to the annexed claims.

I claim 1. In an electromagnet, comprising a magnetic plunger, amagnetic cylinder shell included in the magnetic path of the flux ofsaid electromagnet, a central non-magnetic tube mounted therein andsealed in the ends of said shell with closures, two adjacent similarwindings disposed directly on said tube and pole pieces disposed on saidtube, be tween and at the ends of said coils and out of contactmagnetically and structurally with the shell, said tube having an openend through which passes a non-magnetic connection from the plunger tothe device to be operated.

2. In an electromagnet, comprising a magnetic plunger, a magneticcylinder shell included in the magnetic path for the flux of saidelectromagnet, a central non-magnetic tube mounted therein and sealed inthe ends of said shell With closures, tWo adjacent similar windingsdisposed directly on said tube and pole pieces disposed directly on saidtube, between and at the ends of said coils and out of contactmagnetically and struce turally with the shell, the assembly of thecoils and pole pieces being much shorter 10 than the shell, said tubehaving an open end through which passes a connection from the plunger tothe device to be operated.

In testimony whereof, I have hereunto set my hand and seal 1922.

JOHN L. MILTON.

this 15th day of April, 15

